Cerium‐catalyzed tandem synthesis of 2‐substituted benzothiazoles in PEG

Abstract

An efficient and convenient condensation reaction of 2-aminothiophenol with aldehydes catalyzed by a catalytic amount of ceric ammonium nitrate in polyethylene glycol was investigated. As a result, a set of diverse 2-substituted benzothiazoles such as 2-phenylbenzothiazole as well as its p-Me, p-NO 2 , p-F, p-Cl, p-Br, o-OMe, p-OMe and 2-furyl, 2-pyridyl and styryl derivatives were obtained in good to excellent yields for 5 h at room temperature. Additionally, the catalyst system was recovered and reused several times without evident loss in activity.

Boron Trioxide–Alumina as a Heterogeneous Catalyst in a Facile Solvent Free One-Pot Synthesis of 3,4-Dihydropyrimidin-2(1H)-Ones

“…As part of our continuing interest in the development of new synthetic methodologies, 26,27 we report that B 2 O 3 /Al 2 O 3 is an efficient heterogeneous catalyst for the synthesis of 3,4dihydropyrimidin-2(1H)-ones by the Biginelli reaction under solvent-free conditions.…”

Ultrasound Assisted Ring-Opening Reaction of Epoxides with 1,2-DiphenylDiselenide

“…Cheng) epoxides with 1,2-diphenyldiselenide and the synthesis of βhydroxy selenides in PEG-400 have not yet been investigated systematically. As a continuation of our research in this area, 29 we report here a practical and efficient synthesis of β-hydroxy selenides by ring-opening reaction of epoxides with 1,2diphenyldiselenide (Scheme 1).…”